Dynamic Sustainable Polyimide Film Combining Hardness with Softness via a "Mimosa-like" Bionic Strategy.

Dielectric polyimides are ubiquitous as insulation in electrical power systems and electronic devices. Generally, dynamic polyimide is required to solve electrical or mechanical damage et al. irreversible failure processes under high temperature, pressure and field strength. The challenge lies in the design of the molecular structure of rigid polyimide to achieve dynamic reversibility. Herein, a low molecular weight polyimide gene unit is designed to crosslink with polyimide ligase to prepare the smart film. Interestingly, due to the variability of gene unit and ligase combinations, the polyimide films combining hardness with softness are designed into three forms via a "Mimosa-like" bionic strategy to adapt to different application scenarios. Meanwhile, the films have good degradation efficiency, excellent recyclability and can self-healable, which makes them reuse. Clearly, the films can be used in the preparation of ultra-fast sensors with response time ∼0.15 s and the application of corona resistant films with 100% recovery. Furthermore, the construction of PI and carbon fiber reinforced composites have been verified to apply to the worse environment. Nicely, the composites have the property of multiple cycles and the non-destructive recycle rate of carbon fiber is as high as 100%. Design idea of preparing high strength dynamic polyimide by crosslinking simple polyimide gene unit with ligase could provide a good foundation and a clear case for the sustainable development of electrical and electronic polyimides, from the fancy perspective of Mimosa bionics. This article is protected by copyright. All rights reserved.